native_camera_view 0.0.16

A Flutter plugin for custom native camera integration. Supports image capture, camera switching, pause/resume, and unique capture of the last frame when paused on iOS & Android.

📷 Native Camera View - Flutter Plugin

A Flutter plugin to display a native camera preview for Android and iOS, along with comprehensive camera controls. The plugin uses AndroidView (Android) and UiKitView (iOS) to embed the native camera view directly into the Flutter widget tree for high performance.

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✨ Features

• High-Performance Native Preview: Directly embeds the device's camera feed for a smooth, lag-free live preview.
• Android & iOS Support: Tailored implementations for both Android (using CameraX) and iOS (using AVFoundation).
• Full Resolution & Quality Control:
  • Preview Preset (previewPreset): Set a target resolution for the live preview (low, medium, high, max).
  • Capture Preset (capturePreset): Set a target resolution for the final photo (low, medium, high, max).
  • Capture Mode (captureMode): Optimize for speed (minimizeLatency) or quality (maximizeQuality). maximizeQuality enables advanced post-processing like HDR and noise reduction.
• Still Image Capture: Saves the image to the app's cache folder and returns the file path.
• Advanced Pause/Resume:
  • iOS: Pausing freezes the preview on its last visible frame. This exact frame can be captured even while "paused". The underlying camera session is suspended to save battery.
  • Android: Pausing unbinds the Preview use case (stops the feed) while keeping the ImageCapture use case active.
• Front/Back Camera Switching: Easily toggle between front and back cameras.
• Flexible Preview Scaling & Fit Modes: cover, contain, fitWidth, fitHeight.
  • cover: Scales the preview to completely fill the view. If aspect ratios differ, the video is cropped to fit.
    • ✨ WYSIWYG Capture: Photos taken in cover mode are automatically cropped to precisely match what the user saw, ensuring a "What You See Is What You Get" experience on both platforms.
  • contain: Scales the preview to fit entirely within the view, maintaining its aspect ratio. This may result in "letterboxing" (empty bars).
  • fitWidth / fitHeight: Additional scaling options to fit by width or height.
• Focus Management:
  • Supports continuous auto-focus on both platforms.
  • Android (beta): Includes tap-to-focus interaction.
• Clear Cached Images (Beta): Provides a utility to delete all photos captured by this plugin from the cache directory.

🚀 Installation

iOS

Add the following keys to your ios/Runner/Info.plist file:

<key>NSCameraUsageDescription</key>
<string>This app needs camera access to preview and capture photos.</string>
<key>NSPhotoLibraryUsageDescription</key>
<string>This app needs access to the photo library to save your photos.</string>
<key>NSPhotoLibraryAddUsageDescription</key>
<string>This app needs permission to add photos to your library.</string>

Android

• Minimum API Level: 21 (Android 5.0 - due to CameraX usage)

Add the following permission to your android/app/src/main/AndroidManifest.xml:

<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" android:required="true" />

🛠️ How to Use

1. Add Dependency

dependencies:
  flutter:
    sdk: flutter
  native_camera_view: ^0.0.15 # Replace with the latest version

Run:

flutter pub get

2. Import Plugin

import 'package:native_camera_view/native_camera_view.dart';

3. Use NativeCameraView

Here is a full example of using the NativeCameraView in a StatefulWidget

import 'package.flutter/material.dart';
import 'package.native_camera_view/native_camera_view.dart';

class CameraScreen extends StatefulWidget {
  const CameraScreen({super.key});

  @override
  State<CameraScreen> createState() => _CameraScreenState();
}

class _CameraScreenState extends State<CameraScreen> {
  CameraController? _cameraController;
  bool _isFrontCamera = false;

  void _onCameraControllerCreated(CameraController controller) {
    setState(() {
      _cameraController = controller;
    });
    print("Example App: CameraController created!");
  }

  Future<void> _captureImage() async {
    if (_cameraController == null) return;
    try {
      final path = await _cameraController?.captureImage();
      print("Image captured at: $path");
      // Show the image, e.g., in a new screen
    } catch (e) {
      print("Failed to capture image: $e");
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text("Camera Example")),
      body: Stack(
        children: [
          NativeCameraView(
            onControllerCreated: _onCameraControllerCreated,
            cameraPreviewFit: CameraPreviewFit.cover,
            isFrontCamera: _isFrontCamera,
            // --- Quality Settings ---
            previewPreset: CameraResolutionPreset.high,
            capturePreset: CameraResolutionPreset.max,
            captureMode: CameraCaptureMode.maximizeQuality,
            // --- Optional ---
            loadingWidget: const Center(child: CircularProgressIndicator()),
          ),
          Positioned(
            bottom: 30,
            left: 0,
            right: 0,
            child: FloatingActionButton(
              onPressed: _cameraController == null ? null : _captureImage,
              child: const Icon(Icons.camera_alt),
            ),
          ),
        ],
      ),
    );
  }
}

⚙️ Enums & Parameters

Enums

These enums control the quality and behavior of the camera.

• CameraResolutionPreset:

  • low (e.g., 640x480)
  • medium (e.g., 1280x720)
  • high (e.g., 1920x1080)
  • max (Uses the highest available resolution)

• CameraCaptureMode:

  • minimizeLatency: Prioritizes capture speed. Disables most post-processing.

  • maximizeQuality: Prioritizes photo quality. Enables post-processing like HDR and noise reduction.

• CameraPreviewFit:

  • cover, contain, fitWidth, fitHeight

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📦 NativeCameraView Parameters

Parameter	Type	Description
onControllerCreated	Function(CameraController)	Required. Callback that returns the CameraController once the native view is initialized.
cameraPreviewFit	CameraPreviewFit?	How the preview should be scaled. Default: cover.
isFrontCamera	bool?	Whether to initially open the front camera. Default: false.
previewPreset	CameraResolutionPreset?	Target resolution for the preview stream. Default: null (system default).
captureMode	CameraCaptureMode?	Optimization mode for capturing photos. Default: minimizeLatency.
loadingWidget	Widget?	A custom widget to display while the camera is initializing.
bypassPermissionCheck	bool?	(Advanced) Bypasses the default permission request logic. Default: false.

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📦 CameraController API

// Capture a new photo. Returns the file path.
final String? path = await _cameraController?.captureImage();

// Pause the camera preview.
await _cameraController?.pauseCamera();

// Resume the camera preview.
await _cameraController?.resumeCamera();

// Switch between front (true) and back (false) cameras.
await _cameraController?.switchCamera(bool useFrontCamera);

// Delete all photos previously captured by this plugin.
await _cameraController?.deleteAllCapturedPhotos();

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🐞 Bug Reports & Contributions

Please report issues or contribute at:

🔗 https://github.com/nat0108/Native-camera-view

✉️ [e-mail]